| /* | 
 |  * Copyright (C) 2010 The Android Open Source Project | 
 |  * | 
 |  * Licensed under the Apache License, Version 2.0 (the "License"); | 
 |  * you may not use this file except in compliance with the License. | 
 |  * You may obtain a copy of the License at | 
 |  * | 
 |  *      http://www.apache.org/licenses/LICENSE-2.0 | 
 |  * | 
 |  * Unless required by applicable law or agreed to in writing, software | 
 |  * distributed under the License is distributed on an "AS IS" BASIS, | 
 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | 
 |  * See the License for the specific language governing permissions and | 
 |  * limitations under the License. | 
 |  */ | 
 |  | 
 | package android.nfc; | 
 |  | 
 | import android.annotation.NonNull; | 
 | import android.annotation.RequiresPermission; | 
 | import android.annotation.SdkConstant; | 
 | import android.annotation.SdkConstant.SdkConstantType; | 
 | import android.annotation.SystemApi; | 
 | import android.annotation.UnsupportedAppUsage; | 
 | import android.app.Activity; | 
 | import android.app.ActivityThread; | 
 | import android.app.OnActivityPausedListener; | 
 | import android.app.PendingIntent; | 
 | import android.content.Context; | 
 | import android.content.IntentFilter; | 
 | import android.content.pm.IPackageManager; | 
 | import android.content.pm.PackageManager; | 
 | import android.net.Uri; | 
 | import android.nfc.tech.MifareClassic; | 
 | import android.nfc.tech.Ndef; | 
 | import android.nfc.tech.NfcA; | 
 | import android.nfc.tech.NfcF; | 
 | import android.os.Bundle; | 
 | import android.os.Handler; | 
 | import android.os.IBinder; | 
 | import android.os.RemoteException; | 
 | import android.os.ServiceManager; | 
 | import android.util.Log; | 
 |  | 
 | import java.io.IOException; | 
 | import java.util.ArrayList; | 
 | import java.util.HashMap; | 
 | import java.util.List; | 
 |  | 
 | /** | 
 |  * Represents the local NFC adapter. | 
 |  * <p> | 
 |  * Use the helper {@link #getDefaultAdapter(Context)} to get the default NFC | 
 |  * adapter for this Android device. | 
 |  * | 
 |  * <div class="special reference"> | 
 |  * <h3>Developer Guides</h3> | 
 |  * <p>For more information about using NFC, read the | 
 |  * <a href="{@docRoot}guide/topics/nfc/index.html">Near Field Communication</a> developer guide.</p> | 
 |  * <p>To perform basic file sharing between devices, read | 
 |  * <a href="{@docRoot}training/beam-files/index.html">Sharing Files with NFC</a>. | 
 |  * </div> | 
 |  */ | 
 | public final class NfcAdapter { | 
 |     static final String TAG = "NFC"; | 
 |  | 
 |     /** | 
 |      * Intent to start an activity when a tag with NDEF payload is discovered. | 
 |      * | 
 |      * <p>The system inspects the first {@link NdefRecord} in the first {@link NdefMessage} and | 
 |      * looks for a URI, SmartPoster, or MIME record. If a URI or SmartPoster record is found the | 
 |      * intent will contain the URI in its data field. If a MIME record is found the intent will | 
 |      * contain the MIME type in its type field. This allows activities to register | 
 |      * {@link IntentFilter}s targeting specific content on tags. Activities should register the | 
 |      * most specific intent filters possible to avoid the activity chooser dialog, which can | 
 |      * disrupt the interaction with the tag as the user interacts with the screen. | 
 |      * | 
 |      * <p>If the tag has an NDEF payload this intent is started before | 
 |      * {@link #ACTION_TECH_DISCOVERED}. If any activities respond to this intent neither | 
 |      * {@link #ACTION_TECH_DISCOVERED} or {@link #ACTION_TAG_DISCOVERED} will be started. | 
 |      * | 
 |      * <p>The MIME type or data URI of this intent are normalized before dispatch - | 
 |      * so that MIME, URI scheme and URI host are always lower-case. | 
 |      */ | 
 |     @SdkConstant(SdkConstantType.ACTIVITY_INTENT_ACTION) | 
 |     public static final String ACTION_NDEF_DISCOVERED = "android.nfc.action.NDEF_DISCOVERED"; | 
 |  | 
 |     /** | 
 |      * Intent to start an activity when a tag is discovered and activities are registered for the | 
 |      * specific technologies on the tag. | 
 |      * | 
 |      * <p>To receive this intent an activity must include an intent filter | 
 |      * for this action and specify the desired tech types in a | 
 |      * manifest <code>meta-data</code> entry. Here is an example manfiest entry: | 
 |      * <pre> | 
 |      * <activity android:name=".nfc.TechFilter" android:label="NFC/TechFilter"> | 
 |      *     <!-- Add a technology filter --> | 
 |      *     <intent-filter> | 
 |      *         <action android:name="android.nfc.action.TECH_DISCOVERED" /> | 
 |      *     </intent-filter> | 
 |      * | 
 |      *     <meta-data android:name="android.nfc.action.TECH_DISCOVERED" | 
 |      *         android:resource="@xml/filter_nfc" | 
 |      *     /> | 
 |      * </activity></pre> | 
 |      * | 
 |      * <p>The meta-data XML file should contain one or more <code>tech-list</code> entries | 
 |      * each consisting or one or more <code>tech</code> entries. The <code>tech</code> entries refer | 
 |      * to the qualified class name implementing the technology, for example "android.nfc.tech.NfcA". | 
 |      * | 
 |      * <p>A tag matches if any of the | 
 |      * <code>tech-list</code> sets is a subset of {@link Tag#getTechList() Tag.getTechList()}. Each | 
 |      * of the <code>tech-list</code>s is considered independently and the | 
 |      * activity is considered a match is any single <code>tech-list</code> matches the tag that was | 
 |      * discovered. This provides AND and OR semantics for filtering desired techs. Here is an | 
 |      * example that will match any tag using {@link NfcF} or any tag using {@link NfcA}, | 
 |      * {@link MifareClassic}, and {@link Ndef}: | 
 |      * | 
 |      * <pre> | 
 |      * <resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2"> | 
 |      *     <!-- capture anything using NfcF --> | 
 |      *     <tech-list> | 
 |      *         <tech>android.nfc.tech.NfcF</tech> | 
 |      *     </tech-list> | 
 |      * | 
 |      *     <!-- OR --> | 
 |      * | 
 |      *     <!-- capture all MIFARE Classics with NDEF payloads --> | 
 |      *     <tech-list> | 
 |      *         <tech>android.nfc.tech.NfcA</tech> | 
 |      *         <tech>android.nfc.tech.MifareClassic</tech> | 
 |      *         <tech>android.nfc.tech.Ndef</tech> | 
 |      *     </tech-list> | 
 |      * </resources></pre> | 
 |      * | 
 |      * <p>This intent is started after {@link #ACTION_NDEF_DISCOVERED} and before | 
 |      * {@link #ACTION_TAG_DISCOVERED}. If any activities respond to {@link #ACTION_NDEF_DISCOVERED} | 
 |      * this intent will not be started. If any activities respond to this intent | 
 |      * {@link #ACTION_TAG_DISCOVERED} will not be started. | 
 |      */ | 
 |     @SdkConstant(SdkConstantType.ACTIVITY_INTENT_ACTION) | 
 |     public static final String ACTION_TECH_DISCOVERED = "android.nfc.action.TECH_DISCOVERED"; | 
 |  | 
 |     /** | 
 |      * Intent to start an activity when a tag is discovered. | 
 |      * | 
 |      * <p>This intent will not be started when a tag is discovered if any activities respond to | 
 |      * {@link #ACTION_NDEF_DISCOVERED} or {@link #ACTION_TECH_DISCOVERED} for the current tag. | 
 |      */ | 
 |     @SdkConstant(SdkConstantType.ACTIVITY_INTENT_ACTION) | 
 |     public static final String ACTION_TAG_DISCOVERED = "android.nfc.action.TAG_DISCOVERED"; | 
 |  | 
 |     /** | 
 |      * Broadcast Action: Intent to notify an application that an transaction event has occurred | 
 |      * on the Secure Element. | 
 |      * | 
 |      * <p>This intent will only be sent if the application has requested permission for | 
 |      * {@link android.Manifest.permission#NFC_TRANSACTION_EVENT} and if the application has the | 
 |      * necessary access to Secure Element which witnessed the particular event. | 
 |      */ | 
 |     @RequiresPermission(android.Manifest.permission.NFC_TRANSACTION_EVENT) | 
 |     @SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION) | 
 |     public static final String ACTION_TRANSACTION_DETECTED = | 
 |             "android.nfc.action.TRANSACTION_DETECTED"; | 
 |  | 
 |     /** | 
 |      * Broadcast to only the activity that handles ACTION_TAG_DISCOVERED | 
 |      * @hide | 
 |      */ | 
 |     public static final String ACTION_TAG_LEFT_FIELD = "android.nfc.action.TAG_LOST"; | 
 |  | 
 |     /** | 
 |      * Mandatory extra containing the {@link Tag} that was discovered for the | 
 |      * {@link #ACTION_NDEF_DISCOVERED}, {@link #ACTION_TECH_DISCOVERED}, and | 
 |      * {@link #ACTION_TAG_DISCOVERED} intents. | 
 |      */ | 
 |     public static final String EXTRA_TAG = "android.nfc.extra.TAG"; | 
 |  | 
 |     /** | 
 |      * Extra containing an array of {@link NdefMessage} present on the discovered tag.<p> | 
 |      * This extra is mandatory for {@link #ACTION_NDEF_DISCOVERED} intents, | 
 |      * and optional for {@link #ACTION_TECH_DISCOVERED}, and | 
 |      * {@link #ACTION_TAG_DISCOVERED} intents.<p> | 
 |      * When this extra is present there will always be at least one | 
 |      * {@link NdefMessage} element. Most NDEF tags have only one NDEF message, | 
 |      * but we use an array for future compatibility. | 
 |      */ | 
 |     public static final String EXTRA_NDEF_MESSAGES = "android.nfc.extra.NDEF_MESSAGES"; | 
 |  | 
 |     /** | 
 |      * Optional extra containing a byte array containing the ID of the discovered tag for | 
 |      * the {@link #ACTION_NDEF_DISCOVERED}, {@link #ACTION_TECH_DISCOVERED}, and | 
 |      * {@link #ACTION_TAG_DISCOVERED} intents. | 
 |      */ | 
 |     public static final String EXTRA_ID = "android.nfc.extra.ID"; | 
 |  | 
 |     /** | 
 |      * Broadcast Action: The state of the local NFC adapter has been | 
 |      * changed. | 
 |      * <p>For example, NFC has been turned on or off. | 
 |      * <p>Always contains the extra field {@link #EXTRA_ADAPTER_STATE} | 
 |      */ | 
 |     @SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION) | 
 |     public static final String ACTION_ADAPTER_STATE_CHANGED = | 
 |             "android.nfc.action.ADAPTER_STATE_CHANGED"; | 
 |  | 
 |     /** | 
 |      * Used as an int extra field in {@link #ACTION_ADAPTER_STATE_CHANGED} | 
 |      * intents to request the current power state. Possible values are: | 
 |      * {@link #STATE_OFF}, | 
 |      * {@link #STATE_TURNING_ON}, | 
 |      * {@link #STATE_ON}, | 
 |      * {@link #STATE_TURNING_OFF}, | 
 |      */ | 
 |     public static final String EXTRA_ADAPTER_STATE = "android.nfc.extra.ADAPTER_STATE"; | 
 |  | 
 |     /** | 
 |      * Mandatory byte[] extra field in {@link #ACTION_TRANSACTION_DETECTED} | 
 |      */ | 
 |     public static final String EXTRA_AID = "android.nfc.extra.AID"; | 
 |  | 
 |     /** | 
 |      * Optional byte[] extra field in {@link #ACTION_TRANSACTION_DETECTED} | 
 |      */ | 
 |     public static final String EXTRA_DATA = "android.nfc.extra.DATA"; | 
 |  | 
 |     /** | 
 |      * Mandatory String extra field in {@link #ACTION_TRANSACTION_DETECTED} | 
 |      * Indicates the Secure Element on which the transaction occurred. | 
 |      * eSE1...eSEn for Embedded Secure Elements, SIM1...SIMn for UICC, etc. | 
 |      */ | 
 |     public static final String EXTRA_SECURE_ELEMENT_NAME = "android.nfc.extra.SECURE_ELEMENT_NAME"; | 
 |  | 
 |     public static final int STATE_OFF = 1; | 
 |     public static final int STATE_TURNING_ON = 2; | 
 |     public static final int STATE_ON = 3; | 
 |     public static final int STATE_TURNING_OFF = 4; | 
 |  | 
 |     /** | 
 |      * Flag for use with {@link #enableReaderMode(Activity, ReaderCallback, int, Bundle)}. | 
 |      * <p> | 
 |      * Setting this flag enables polling for Nfc-A technology. | 
 |      */ | 
 |     public static final int FLAG_READER_NFC_A = 0x1; | 
 |  | 
 |     /** | 
 |      * Flag for use with {@link #enableReaderMode(Activity, ReaderCallback, int, Bundle)}. | 
 |      * <p> | 
 |      * Setting this flag enables polling for Nfc-B technology. | 
 |      */ | 
 |     public static final int FLAG_READER_NFC_B = 0x2; | 
 |  | 
 |     /** | 
 |      * Flag for use with {@link #enableReaderMode(Activity, ReaderCallback, int, Bundle)}. | 
 |      * <p> | 
 |      * Setting this flag enables polling for Nfc-F technology. | 
 |      */ | 
 |     public static final int FLAG_READER_NFC_F = 0x4; | 
 |  | 
 |     /** | 
 |      * Flag for use with {@link #enableReaderMode(Activity, ReaderCallback, int, Bundle)}. | 
 |      * <p> | 
 |      * Setting this flag enables polling for Nfc-V (ISO15693) technology. | 
 |      */ | 
 |     public static final int FLAG_READER_NFC_V = 0x8; | 
 |  | 
 |     /** | 
 |      * Flag for use with {@link #enableReaderMode(Activity, ReaderCallback, int, Bundle)}. | 
 |      * <p> | 
 |      * Setting this flag enables polling for NfcBarcode technology. | 
 |      */ | 
 |     public static final int FLAG_READER_NFC_BARCODE = 0x10; | 
 |  | 
 |     /** | 
 |      * Flag for use with {@link #enableReaderMode(Activity, ReaderCallback, int, Bundle)}. | 
 |      * <p> | 
 |      * Setting this flag allows the caller to prevent the | 
 |      * platform from performing an NDEF check on the tags it | 
 |      * finds. | 
 |      */ | 
 |     public static final int FLAG_READER_SKIP_NDEF_CHECK = 0x80; | 
 |  | 
 |     /** | 
 |      * Flag for use with {@link #enableReaderMode(Activity, ReaderCallback, int, Bundle)}. | 
 |      * <p> | 
 |      * Setting this flag allows the caller to prevent the | 
 |      * platform from playing sounds when it discovers a tag. | 
 |      */ | 
 |     public static final int FLAG_READER_NO_PLATFORM_SOUNDS = 0x100; | 
 |  | 
 |     /** | 
 |      * Int Extra for use with {@link #enableReaderMode(Activity, ReaderCallback, int, Bundle)}. | 
 |      * <p> | 
 |      * Setting this integer extra allows the calling application to specify | 
 |      * the delay that the platform will use for performing presence checks | 
 |      * on any discovered tag. | 
 |      */ | 
 |     public static final String EXTRA_READER_PRESENCE_CHECK_DELAY = "presence"; | 
 |  | 
 |     /** @hide */ | 
 |     @SystemApi | 
 |     public static final int FLAG_NDEF_PUSH_NO_CONFIRM = 0x1; | 
 |  | 
 |     /** @hide */ | 
 |     public static final String ACTION_HANDOVER_TRANSFER_STARTED = | 
 |             "android.nfc.action.HANDOVER_TRANSFER_STARTED"; | 
 |  | 
 |     /** @hide */ | 
 |     public static final String ACTION_HANDOVER_TRANSFER_DONE = | 
 |             "android.nfc.action.HANDOVER_TRANSFER_DONE"; | 
 |  | 
 |     /** @hide */ | 
 |     public static final String EXTRA_HANDOVER_TRANSFER_STATUS = | 
 |             "android.nfc.extra.HANDOVER_TRANSFER_STATUS"; | 
 |  | 
 |     /** @hide */ | 
 |     public static final int HANDOVER_TRANSFER_STATUS_SUCCESS = 0; | 
 |     /** @hide */ | 
 |     public static final int HANDOVER_TRANSFER_STATUS_FAILURE = 1; | 
 |  | 
 |     /** @hide */ | 
 |     public static final String EXTRA_HANDOVER_TRANSFER_URI = | 
 |             "android.nfc.extra.HANDOVER_TRANSFER_URI"; | 
 |  | 
 |     // Guarded by NfcAdapter.class | 
 |     static boolean sIsInitialized = false; | 
 |     static boolean sHasNfcFeature; | 
 |     static boolean sHasBeamFeature; | 
 |  | 
 |     // Final after first constructor, except for | 
 |     // attemptDeadServiceRecovery() when NFC crashes - we accept a best effort | 
 |     // recovery | 
 |     @UnsupportedAppUsage | 
 |     static INfcAdapter sService; | 
 |     static INfcTag sTagService; | 
 |     static INfcCardEmulation sCardEmulationService; | 
 |     static INfcFCardEmulation sNfcFCardEmulationService; | 
 |  | 
 |     /** | 
 |      * The NfcAdapter object for each application context. | 
 |      * There is a 1-1 relationship between application context and | 
 |      * NfcAdapter object. | 
 |      */ | 
 |     static HashMap<Context, NfcAdapter> sNfcAdapters = new HashMap(); //guard by NfcAdapter.class | 
 |  | 
 |     /** | 
 |      * NfcAdapter used with a null context. This ctor was deprecated but we have | 
 |      * to support it for backwards compatibility. New methods that require context | 
 |      * might throw when called on the null-context NfcAdapter. | 
 |      */ | 
 |     static NfcAdapter sNullContextNfcAdapter;  // protected by NfcAdapter.class | 
 |  | 
 |     final NfcActivityManager mNfcActivityManager; | 
 |     final Context mContext; | 
 |     final HashMap<NfcUnlockHandler, INfcUnlockHandler> mNfcUnlockHandlers; | 
 |     final Object mLock; | 
 |  | 
 |     ITagRemovedCallback mTagRemovedListener; // protected by mLock | 
 |  | 
 |     /** | 
 |      * A callback to be invoked when the system finds a tag while the foreground activity is | 
 |      * operating in reader mode. | 
 |      * <p>Register your {@code ReaderCallback} implementation with {@link | 
 |      * NfcAdapter#enableReaderMode} and disable it with {@link | 
 |      * NfcAdapter#disableReaderMode}. | 
 |      * @see NfcAdapter#enableReaderMode | 
 |      */ | 
 |     public interface ReaderCallback { | 
 |         public void onTagDiscovered(Tag tag); | 
 |     } | 
 |  | 
 |     /** | 
 |      * A callback to be invoked when the system successfully delivers your {@link NdefMessage} | 
 |      * to another device. | 
 |      * @see #setOnNdefPushCompleteCallback | 
 |      * @deprecated this feature is deprecated. File sharing can work using other technology like | 
 |      * Bluetooth. | 
 |      */ | 
 |     @java.lang.Deprecated | 
 |     public interface OnNdefPushCompleteCallback { | 
 |         /** | 
 |          * Called on successful NDEF push. | 
 |          * | 
 |          * <p>This callback is usually made on a binder thread (not the UI thread). | 
 |          * | 
 |          * @param event {@link NfcEvent} with the {@link NfcEvent#nfcAdapter} field set | 
 |          * @see #setNdefPushMessageCallback | 
 |          */ | 
 |         public void onNdefPushComplete(NfcEvent event); | 
 |     } | 
 |  | 
 |     /** | 
 |      * A callback to be invoked when another NFC device capable of NDEF push (Android Beam) | 
 |      * is within range. | 
 |      * <p>Implement this interface and pass it to {@link | 
 |      * NfcAdapter#setNdefPushMessageCallback setNdefPushMessageCallback()} in order to create an | 
 |      * {@link NdefMessage} at the moment that another device is within range for NFC. Using this | 
 |      * callback allows you to create a message with data that might vary based on the | 
 |      * content currently visible to the user. Alternatively, you can call {@link | 
 |      * #setNdefPushMessage setNdefPushMessage()} if the {@link NdefMessage} always contains the | 
 |      * same data. | 
 |      * @deprecated this feature is deprecated. File sharing can work using other technology like | 
 |      * Bluetooth. | 
 |      */ | 
 |     @java.lang.Deprecated | 
 |     public interface CreateNdefMessageCallback { | 
 |         /** | 
 |          * Called to provide a {@link NdefMessage} to push. | 
 |          * | 
 |          * <p>This callback is usually made on a binder thread (not the UI thread). | 
 |          * | 
 |          * <p>Called when this device is in range of another device | 
 |          * that might support NDEF push. It allows the application to | 
 |          * create the NDEF message only when it is required. | 
 |          * | 
 |          * <p>NDEF push cannot occur until this method returns, so do not | 
 |          * block for too long. | 
 |          * | 
 |          * <p>The Android operating system will usually show a system UI | 
 |          * on top of your activity during this time, so do not try to request | 
 |          * input from the user to complete the callback, or provide custom NDEF | 
 |          * push UI. The user probably will not see it. | 
 |          * | 
 |          * @param event {@link NfcEvent} with the {@link NfcEvent#nfcAdapter} field set | 
 |          * @return NDEF message to push, or null to not provide a message | 
 |          */ | 
 |         public NdefMessage createNdefMessage(NfcEvent event); | 
 |     } | 
 |  | 
 |  | 
 |      /** | 
 |      * @deprecated this feature is deprecated. File sharing can work using other technology like | 
 |      * Bluetooth. | 
 |      */ | 
 |     @java.lang.Deprecated | 
 |     public interface CreateBeamUrisCallback { | 
 |         public Uri[] createBeamUris(NfcEvent event); | 
 |     } | 
 |  | 
 |     /** | 
 |      * A callback that is invoked when a tag is removed from the field. | 
 |      * @see NfcAdapter#ignore | 
 |      */ | 
 |     public interface OnTagRemovedListener { | 
 |         void onTagRemoved(); | 
 |     } | 
 |  | 
 |     /** | 
 |      * A callback to be invoked when an application has registered as a | 
 |      * handler to unlock the device given an NFC tag at the lockscreen. | 
 |      * @hide | 
 |      */ | 
 |     @SystemApi | 
 |     public interface NfcUnlockHandler { | 
 |         /** | 
 |          * Called at the lock screen to attempt to unlock the device with the given tag. | 
 |          * @param tag the detected tag, to be used to unlock the device | 
 |          * @return true if the device was successfully unlocked | 
 |          */ | 
 |         public boolean onUnlockAttempted(Tag tag); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Helper to check if this device has FEATURE_NFC_BEAM, but without using | 
 |      * a context. | 
 |      * Equivalent to | 
 |      * context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_NFC_BEAM) | 
 |      */ | 
 |     private static boolean hasBeamFeature() { | 
 |         IPackageManager pm = ActivityThread.getPackageManager(); | 
 |         if (pm == null) { | 
 |             Log.e(TAG, "Cannot get package manager, assuming no Android Beam feature"); | 
 |             return false; | 
 |         } | 
 |         try { | 
 |             return pm.hasSystemFeature(PackageManager.FEATURE_NFC_BEAM, 0); | 
 |         } catch (RemoteException e) { | 
 |             Log.e(TAG, "Package manager query failed, assuming no Android Beam feature", e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Helper to check if this device has FEATURE_NFC, but without using | 
 |      * a context. | 
 |      * Equivalent to | 
 |      * context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_NFC) | 
 |      */ | 
 |     private static boolean hasNfcFeature() { | 
 |         IPackageManager pm = ActivityThread.getPackageManager(); | 
 |         if (pm == null) { | 
 |             Log.e(TAG, "Cannot get package manager, assuming no NFC feature"); | 
 |             return false; | 
 |         } | 
 |         try { | 
 |             return pm.hasSystemFeature(PackageManager.FEATURE_NFC, 0); | 
 |         } catch (RemoteException e) { | 
 |             Log.e(TAG, "Package manager query failed, assuming no NFC feature", e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Helper to check if this device is NFC HCE capable, by checking for | 
 |      * FEATURE_NFC_HOST_CARD_EMULATION and/or FEATURE_NFC_HOST_CARD_EMULATION_NFCF, | 
 |      * but without using a context. | 
 |      */ | 
 |     private static boolean hasNfcHceFeature() { | 
 |         IPackageManager pm = ActivityThread.getPackageManager(); | 
 |         if (pm == null) { | 
 |             Log.e(TAG, "Cannot get package manager, assuming no NFC feature"); | 
 |             return false; | 
 |         } | 
 |         try { | 
 |             return pm.hasSystemFeature(PackageManager.FEATURE_NFC_HOST_CARD_EMULATION, 0) | 
 |                 || pm.hasSystemFeature(PackageManager.FEATURE_NFC_HOST_CARD_EMULATION_NFCF, 0); | 
 |         } catch (RemoteException e) { | 
 |             Log.e(TAG, "Package manager query failed, assuming no NFC feature", e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Return list of Secure Elements which support off host card emulation. | 
 |      * | 
 |      * @return List<String> containing secure elements on the device which supports | 
 |      *                      off host card emulation. eSE for Embedded secure element, | 
 |      *                      SIM for UICC and so on. | 
 |      * @hide | 
 |      */ | 
 |     public @NonNull List<String> getSupportedOffHostSecureElements() { | 
 |         List<String> offHostSE = new ArrayList<String>(); | 
 |         IPackageManager pm = ActivityThread.getPackageManager(); | 
 |         if (pm == null) { | 
 |             Log.e(TAG, "Cannot get package manager, assuming no off-host CE feature"); | 
 |             return offHostSE; | 
 |         } | 
 |         try { | 
 |             if (pm.hasSystemFeature(PackageManager.FEATURE_NFC_OFF_HOST_CARD_EMULATION_UICC, 0)) { | 
 |                 offHostSE.add("SIM"); | 
 |             } | 
 |             if (pm.hasSystemFeature(PackageManager.FEATURE_NFC_OFF_HOST_CARD_EMULATION_ESE, 0)) { | 
 |                 offHostSE.add("eSE"); | 
 |             } | 
 |         } catch (RemoteException e) { | 
 |             Log.e(TAG, "Package manager query failed, assuming no off-host CE feature", e); | 
 |             offHostSE.clear(); | 
 |             return offHostSE; | 
 |         } | 
 |         return offHostSE; | 
 |     } | 
 |  | 
 |     /** | 
 |      * Returns the NfcAdapter for application context, | 
 |      * or throws if NFC is not available. | 
 |      * @hide | 
 |      */ | 
 |     @UnsupportedAppUsage | 
 |     public static synchronized NfcAdapter getNfcAdapter(Context context) { | 
 |         if (!sIsInitialized) { | 
 |             sHasNfcFeature = hasNfcFeature(); | 
 |             sHasBeamFeature = hasBeamFeature(); | 
 |             boolean hasHceFeature = hasNfcHceFeature(); | 
 |             /* is this device meant to have NFC */ | 
 |             if (!sHasNfcFeature && !hasHceFeature) { | 
 |                 Log.v(TAG, "this device does not have NFC support"); | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |             sService = getServiceInterface(); | 
 |             if (sService == null) { | 
 |                 Log.e(TAG, "could not retrieve NFC service"); | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |             if (sHasNfcFeature) { | 
 |                 try { | 
 |                     sTagService = sService.getNfcTagInterface(); | 
 |                 } catch (RemoteException e) { | 
 |                     Log.e(TAG, "could not retrieve NFC Tag service"); | 
 |                     throw new UnsupportedOperationException(); | 
 |                 } | 
 |             } | 
 |             if (hasHceFeature) { | 
 |                 try { | 
 |                     sNfcFCardEmulationService = sService.getNfcFCardEmulationInterface(); | 
 |                 } catch (RemoteException e) { | 
 |                     Log.e(TAG, "could not retrieve NFC-F card emulation service"); | 
 |                     throw new UnsupportedOperationException(); | 
 |                 } | 
 |                 try { | 
 |                     sCardEmulationService = sService.getNfcCardEmulationInterface(); | 
 |                 } catch (RemoteException e) { | 
 |                     Log.e(TAG, "could not retrieve card emulation service"); | 
 |                     throw new UnsupportedOperationException(); | 
 |                 } | 
 |             } | 
 |  | 
 |             sIsInitialized = true; | 
 |         } | 
 |         if (context == null) { | 
 |             if (sNullContextNfcAdapter == null) { | 
 |                 sNullContextNfcAdapter = new NfcAdapter(null); | 
 |             } | 
 |             return sNullContextNfcAdapter; | 
 |         } | 
 |         NfcAdapter adapter = sNfcAdapters.get(context); | 
 |         if (adapter == null) { | 
 |             adapter = new NfcAdapter(context); | 
 |             sNfcAdapters.put(context, adapter); | 
 |         } | 
 |         return adapter; | 
 |     } | 
 |  | 
 |     /** get handle to NFC service interface */ | 
 |     private static INfcAdapter getServiceInterface() { | 
 |         /* get a handle to NFC service */ | 
 |         IBinder b = ServiceManager.getService("nfc"); | 
 |         if (b == null) { | 
 |             return null; | 
 |         } | 
 |         return INfcAdapter.Stub.asInterface(b); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Helper to get the default NFC Adapter. | 
 |      * <p> | 
 |      * Most Android devices will only have one NFC Adapter (NFC Controller). | 
 |      * <p> | 
 |      * This helper is the equivalent of: | 
 |      * <pre> | 
 |      * NfcManager manager = (NfcManager) context.getSystemService(Context.NFC_SERVICE); | 
 |      * NfcAdapter adapter = manager.getDefaultAdapter();</pre> | 
 |      * @param context the calling application's context | 
 |      * | 
 |      * @return the default NFC adapter, or null if no NFC adapter exists | 
 |      */ | 
 |     public static NfcAdapter getDefaultAdapter(Context context) { | 
 |         if (context == null) { | 
 |             throw new IllegalArgumentException("context cannot be null"); | 
 |         } | 
 |         context = context.getApplicationContext(); | 
 |         if (context == null) { | 
 |             throw new IllegalArgumentException( | 
 |                     "context not associated with any application (using a mock context?)"); | 
 |         } | 
 |         /* use getSystemService() for consistency */ | 
 |         NfcManager manager = (NfcManager) context.getSystemService(Context.NFC_SERVICE); | 
 |         if (manager == null) { | 
 |             // NFC not available | 
 |             return null; | 
 |         } | 
 |         return manager.getDefaultAdapter(); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Legacy NfcAdapter getter, always use {@link #getDefaultAdapter(Context)} instead.<p> | 
 |      * This method was deprecated at API level 10 (Gingerbread MR1) because a context is required | 
 |      * for many NFC API methods. Those methods will fail when called on an NfcAdapter | 
 |      * object created from this method.<p> | 
 |      * @deprecated use {@link #getDefaultAdapter(Context)} | 
 |      * @hide | 
 |      */ | 
 |     @Deprecated | 
 |     @UnsupportedAppUsage | 
 |     public static NfcAdapter getDefaultAdapter() { | 
 |         // introduced in API version 9 (GB 2.3) | 
 |         // deprecated in API version 10 (GB 2.3.3) | 
 |         // removed from public API in version 16 (ICS MR2) | 
 |         // should maintain as a hidden API for binary compatibility for a little longer | 
 |         Log.w(TAG, "WARNING: NfcAdapter.getDefaultAdapter() is deprecated, use " + | 
 |                 "NfcAdapter.getDefaultAdapter(Context) instead", new Exception()); | 
 |  | 
 |         return NfcAdapter.getNfcAdapter(null); | 
 |     } | 
 |  | 
 |     NfcAdapter(Context context) { | 
 |         mContext = context; | 
 |         mNfcActivityManager = new NfcActivityManager(this); | 
 |         mNfcUnlockHandlers = new HashMap<NfcUnlockHandler, INfcUnlockHandler>(); | 
 |         mTagRemovedListener = null; | 
 |         mLock = new Object(); | 
 |     } | 
 |  | 
 |     /** | 
 |      * @hide | 
 |      */ | 
 |     @UnsupportedAppUsage | 
 |     public Context getContext() { | 
 |         return mContext; | 
 |     } | 
 |  | 
 |     /** | 
 |      * Returns the binder interface to the service. | 
 |      * @hide | 
 |      */ | 
 |     @UnsupportedAppUsage | 
 |     public INfcAdapter getService() { | 
 |         isEnabled();  // NOP call to recover sService if it is stale | 
 |         return sService; | 
 |     } | 
 |  | 
 |     /** | 
 |      * Returns the binder interface to the tag service. | 
 |      * @hide | 
 |      */ | 
 |     public INfcTag getTagService() { | 
 |         isEnabled();  // NOP call to recover sTagService if it is stale | 
 |         return sTagService; | 
 |     } | 
 |  | 
 |     /** | 
 |      * Returns the binder interface to the card emulation service. | 
 |      * @hide | 
 |      */ | 
 |     public INfcCardEmulation getCardEmulationService() { | 
 |         isEnabled(); | 
 |         return sCardEmulationService; | 
 |     } | 
 |  | 
 |     /** | 
 |      * Returns the binder interface to the NFC-F card emulation service. | 
 |      * @hide | 
 |      */ | 
 |     public INfcFCardEmulation getNfcFCardEmulationService() { | 
 |         isEnabled(); | 
 |         return sNfcFCardEmulationService; | 
 |     } | 
 |  | 
 |     /** | 
 |      * Returns the binder interface to the NFC-DTA test interface. | 
 |      * @hide | 
 |      */ | 
 |     public INfcDta getNfcDtaInterface() { | 
 |         if (mContext == null) { | 
 |             throw new UnsupportedOperationException("You need a context on NfcAdapter to use the " | 
 |                     + " NFC extras APIs"); | 
 |         } | 
 |         try { | 
 |             return sService.getNfcDtaInterface(mContext.getPackageName()); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return null; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * NFC service dead - attempt best effort recovery | 
 |      * @hide | 
 |      */ | 
 |     @UnsupportedAppUsage | 
 |     public void attemptDeadServiceRecovery(Exception e) { | 
 |         Log.e(TAG, "NFC service dead - attempting to recover", e); | 
 |         INfcAdapter service = getServiceInterface(); | 
 |         if (service == null) { | 
 |             Log.e(TAG, "could not retrieve NFC service during service recovery"); | 
 |             // nothing more can be done now, sService is still stale, we'll hit | 
 |             // this recovery path again later | 
 |             return; | 
 |         } | 
 |         // assigning to sService is not thread-safe, but this is best-effort code | 
 |         // and on a well-behaved system should never happen | 
 |         sService = service; | 
 |         try { | 
 |             sTagService = service.getNfcTagInterface(); | 
 |         } catch (RemoteException ee) { | 
 |             Log.e(TAG, "could not retrieve NFC tag service during service recovery"); | 
 |             // nothing more can be done now, sService is still stale, we'll hit | 
 |             // this recovery path again later | 
 |             return; | 
 |         } | 
 |  | 
 |         try { | 
 |             sCardEmulationService = service.getNfcCardEmulationInterface(); | 
 |         } catch (RemoteException ee) { | 
 |             Log.e(TAG, "could not retrieve NFC card emulation service during service recovery"); | 
 |         } | 
 |  | 
 |         try { | 
 |             sNfcFCardEmulationService = service.getNfcFCardEmulationInterface(); | 
 |         } catch (RemoteException ee) { | 
 |             Log.e(TAG, "could not retrieve NFC-F card emulation service during service recovery"); | 
 |         } | 
 |  | 
 |         return; | 
 |     } | 
 |  | 
 |     /** | 
 |      * Return true if this NFC Adapter has any features enabled. | 
 |      * | 
 |      * <p>If this method returns false, the NFC hardware is guaranteed not to | 
 |      * generate or respond to any NFC communication over its NFC radio. | 
 |      * <p>Applications can use this to check if NFC is enabled. Applications | 
 |      * can request Settings UI allowing the user to toggle NFC using: | 
 |      * <p><pre>startActivity(new Intent(Settings.ACTION_NFC_SETTINGS))</pre> | 
 |      * | 
 |      * @see android.provider.Settings#ACTION_NFC_SETTINGS | 
 |      * @return true if this NFC Adapter has any features enabled | 
 |      */ | 
 |     public boolean isEnabled() { | 
 |         try { | 
 |             return sService.getState() == STATE_ON; | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Return the state of this NFC Adapter. | 
 |      * | 
 |      * <p>Returns one of {@link #STATE_ON}, {@link #STATE_TURNING_ON}, | 
 |      * {@link #STATE_OFF}, {@link #STATE_TURNING_OFF}. | 
 |      * | 
 |      * <p>{@link #isEnabled()} is equivalent to | 
 |      * <code>{@link #getAdapterState()} == {@link #STATE_ON}</code> | 
 |      * | 
 |      * @return the current state of this NFC adapter | 
 |      * | 
 |      * @hide | 
 |      */ | 
 |     @UnsupportedAppUsage | 
 |     public int getAdapterState() { | 
 |         try { | 
 |             return sService.getState(); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return NfcAdapter.STATE_OFF; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Enable NFC hardware. | 
 |      * | 
 |      * <p>This call is asynchronous. Listen for | 
 |      * {@link #ACTION_ADAPTER_STATE_CHANGED} broadcasts to find out when the | 
 |      * operation is complete. | 
 |      * | 
 |      * <p>If this returns true, then either NFC is already on, or | 
 |      * a {@link #ACTION_ADAPTER_STATE_CHANGED} broadcast will be sent | 
 |      * to indicate a state transition. If this returns false, then | 
 |      * there is some problem that prevents an attempt to turn | 
 |      * NFC on (for example we are in airplane mode and NFC is not | 
 |      * toggleable in airplane mode on this platform). | 
 |      * | 
 |      * @hide | 
 |      */ | 
 |     @SystemApi | 
 |     @RequiresPermission(android.Manifest.permission.WRITE_SECURE_SETTINGS) | 
 |     public boolean enable() { | 
 |         try { | 
 |             return sService.enable(); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Disable NFC hardware. | 
 |      * | 
 |      * <p>No NFC features will work after this call, and the hardware | 
 |      * will not perform or respond to any NFC communication. | 
 |      * | 
 |      * <p>This call is asynchronous. Listen for | 
 |      * {@link #ACTION_ADAPTER_STATE_CHANGED} broadcasts to find out when the | 
 |      * operation is complete. | 
 |      * | 
 |      * <p>If this returns true, then either NFC is already off, or | 
 |      * a {@link #ACTION_ADAPTER_STATE_CHANGED} broadcast will be sent | 
 |      * to indicate a state transition. If this returns false, then | 
 |      * there is some problem that prevents an attempt to turn | 
 |      * NFC off. | 
 |      * | 
 |      * @hide | 
 |      */ | 
 |     @SystemApi | 
 |     @RequiresPermission(android.Manifest.permission.WRITE_SECURE_SETTINGS) | 
 |     public boolean disable() { | 
 |         try { | 
 |             return sService.disable(true); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Disable NFC hardware. | 
 |      * @hide | 
 |     */ | 
 |     @SystemApi | 
 |     @RequiresPermission(android.Manifest.permission.WRITE_SECURE_SETTINGS) | 
 |     public boolean disable(boolean persist) { | 
 |         try { | 
 |             return sService.disable(persist); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Pauses polling for a {@code timeoutInMs} millis. If polling must be resumed before timeout, | 
 |      * use {@link #resumePolling()}. | 
 |      * @hide | 
 |      */ | 
 |     public void pausePolling(int timeoutInMs) { | 
 |         try { | 
 |             sService.pausePolling(timeoutInMs); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Resumes default polling for the current device state if polling is paused. Calling | 
 |      * this while polling is not paused is a no-op. | 
 |      * | 
 |      * @hide | 
 |      */ | 
 |     public void resumePolling() { | 
 |         try { | 
 |             sService.resumePolling(); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Set one or more {@link Uri}s to send using Android Beam (TM). Every | 
 |      * Uri you provide must have either scheme 'file' or scheme 'content'. | 
 |      * | 
 |      * <p>For the data provided through this method, Android Beam tries to | 
 |      * switch to alternate transports such as Bluetooth to achieve a fast | 
 |      * transfer speed. Hence this method is very suitable | 
 |      * for transferring large files such as pictures or songs. | 
 |      * | 
 |      * <p>The receiving side will store the content of each Uri in | 
 |      * a file and present a notification to the user to open the file | 
 |      * with a {@link android.content.Intent} with action | 
 |      * {@link android.content.Intent#ACTION_VIEW}. | 
 |      * If multiple URIs are sent, the {@link android.content.Intent} will refer | 
 |      * to the first of the stored files. | 
 |      * | 
 |      * <p>This method may be called at any time before {@link Activity#onDestroy}, | 
 |      * but the URI(s) are only made available for Android Beam when the | 
 |      * specified activity(s) are in resumed (foreground) state. The recommended | 
 |      * approach is to call this method during your Activity's | 
 |      * {@link Activity#onCreate} - see sample | 
 |      * code below. This method does not immediately perform any I/O or blocking work, | 
 |      * so is safe to call on your main thread. | 
 |      * | 
 |      * <p>{@link #setBeamPushUris} and {@link #setBeamPushUrisCallback} | 
 |      * have priority over both {@link #setNdefPushMessage} and | 
 |      * {@link #setNdefPushMessageCallback}. | 
 |      * | 
 |      * <p>If {@link #setBeamPushUris} is called with a null Uri array, | 
 |      * and/or {@link #setBeamPushUrisCallback} is called with a null callback, | 
 |      * then the Uri push will be completely disabled for the specified activity(s). | 
 |      * | 
 |      * <p>Code example: | 
 |      * <pre> | 
 |      * protected void onCreate(Bundle savedInstanceState) { | 
 |      *     super.onCreate(savedInstanceState); | 
 |      *     NfcAdapter nfcAdapter = NfcAdapter.getDefaultAdapter(this); | 
 |      *     if (nfcAdapter == null) return;  // NFC not available on this device | 
 |      *     nfcAdapter.setBeamPushUris(new Uri[] {uri1, uri2}, this); | 
 |      * }</pre> | 
 |      * And that is it. Only one call per activity is necessary. The Android | 
 |      * OS will automatically release its references to the Uri(s) and the | 
 |      * Activity object when it is destroyed if you follow this pattern. | 
 |      * | 
 |      * <p>If your Activity wants to dynamically supply Uri(s), | 
 |      * then set a callback using {@link #setBeamPushUrisCallback} instead | 
 |      * of using this method. | 
 |      * | 
 |      * <p class="note">Do not pass in an Activity that has already been through | 
 |      * {@link Activity#onDestroy}. This is guaranteed if you call this API | 
 |      * during {@link Activity#onCreate}. | 
 |      * | 
 |      * <p class="note">If this device does not support alternate transports | 
 |      * such as Bluetooth or WiFI, calling this method does nothing. | 
 |      * | 
 |      * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission. | 
 |      * | 
 |      * @param uris an array of Uri(s) to push over Android Beam | 
 |      * @param activity activity for which the Uri(s) will be pushed | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      * @deprecated this feature is deprecated. File sharing can work using other technology like | 
 |      * Bluetooth. | 
 |      */ | 
 |     @java.lang.Deprecated | 
 |     public void setBeamPushUris(Uri[] uris, Activity activity) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |             if (!sHasBeamFeature) { | 
 |                 return; | 
 |             } | 
 |         } | 
 |         if (activity == null) { | 
 |             throw new NullPointerException("activity cannot be null"); | 
 |         } | 
 |         if (uris != null) { | 
 |             for (Uri uri : uris) { | 
 |                 if (uri == null) throw new NullPointerException("Uri not " + | 
 |                         "allowed to be null"); | 
 |                 String scheme = uri.getScheme(); | 
 |                 if (scheme == null || (!scheme.equalsIgnoreCase("file") && | 
 |                         !scheme.equalsIgnoreCase("content"))) { | 
 |                     throw new IllegalArgumentException("URI needs to have " + | 
 |                             "either scheme file or scheme content"); | 
 |                 } | 
 |             } | 
 |         } | 
 |         mNfcActivityManager.setNdefPushContentUri(activity, uris); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Set a callback that will dynamically generate one or more {@link Uri}s | 
 |      * to send using Android Beam (TM). Every Uri the callback provides | 
 |      * must have either scheme 'file' or scheme 'content'. | 
 |      * | 
 |      * <p>For the data provided through this callback, Android Beam tries to | 
 |      * switch to alternate transports such as Bluetooth to achieve a fast | 
 |      * transfer speed. Hence this method is very suitable | 
 |      * for transferring large files such as pictures or songs. | 
 |      * | 
 |      * <p>The receiving side will store the content of each Uri in | 
 |      * a file and present a notification to the user to open the file | 
 |      * with a {@link android.content.Intent} with action | 
 |      * {@link android.content.Intent#ACTION_VIEW}. | 
 |      * If multiple URIs are sent, the {@link android.content.Intent} will refer | 
 |      * to the first of the stored files. | 
 |      * | 
 |      * <p>This method may be called at any time before {@link Activity#onDestroy}, | 
 |      * but the URI(s) are only made available for Android Beam when the | 
 |      * specified activity(s) are in resumed (foreground) state. The recommended | 
 |      * approach is to call this method during your Activity's | 
 |      * {@link Activity#onCreate} - see sample | 
 |      * code below. This method does not immediately perform any I/O or blocking work, | 
 |      * so is safe to call on your main thread. | 
 |      * | 
 |      * <p>{@link #setBeamPushUris} and {@link #setBeamPushUrisCallback} | 
 |      * have priority over both {@link #setNdefPushMessage} and | 
 |      * {@link #setNdefPushMessageCallback}. | 
 |      * | 
 |      * <p>If {@link #setBeamPushUris} is called with a null Uri array, | 
 |      * and/or {@link #setBeamPushUrisCallback} is called with a null callback, | 
 |      * then the Uri push will be completely disabled for the specified activity(s). | 
 |      * | 
 |      * <p>Code example: | 
 |      * <pre> | 
 |      * protected void onCreate(Bundle savedInstanceState) { | 
 |      *     super.onCreate(savedInstanceState); | 
 |      *     NfcAdapter nfcAdapter = NfcAdapter.getDefaultAdapter(this); | 
 |      *     if (nfcAdapter == null) return;  // NFC not available on this device | 
 |      *     nfcAdapter.setBeamPushUrisCallback(callback, this); | 
 |      * }</pre> | 
 |      * And that is it. Only one call per activity is necessary. The Android | 
 |      * OS will automatically release its references to the Uri(s) and the | 
 |      * Activity object when it is destroyed if you follow this pattern. | 
 |      * | 
 |      * <p class="note">Do not pass in an Activity that has already been through | 
 |      * {@link Activity#onDestroy}. This is guaranteed if you call this API | 
 |      * during {@link Activity#onCreate}. | 
 |      * | 
 |      * <p class="note">If this device does not support alternate transports | 
 |      * such as Bluetooth or WiFI, calling this method does nothing. | 
 |      * | 
 |      * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission. | 
 |      * | 
 |      * @param callback callback, or null to disable | 
 |      * @param activity activity for which the Uri(s) will be pushed | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      * @deprecated this feature is deprecated. File sharing can work using other technology like | 
 |      * Bluetooth. | 
 |      */ | 
 |     @java.lang.Deprecated | 
 |     public void setBeamPushUrisCallback(CreateBeamUrisCallback callback, Activity activity) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |             if (!sHasBeamFeature) { | 
 |                 return; | 
 |             } | 
 |         } | 
 |         if (activity == null) { | 
 |             throw new NullPointerException("activity cannot be null"); | 
 |         } | 
 |         mNfcActivityManager.setNdefPushContentUriCallback(activity, callback); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Set a static {@link NdefMessage} to send using Android Beam (TM). | 
 |      * | 
 |      * <p>This method may be called at any time before {@link Activity#onDestroy}, | 
 |      * but the NDEF message is only made available for NDEF push when the | 
 |      * specified activity(s) are in resumed (foreground) state. The recommended | 
 |      * approach is to call this method during your Activity's | 
 |      * {@link Activity#onCreate} - see sample | 
 |      * code below. This method does not immediately perform any I/O or blocking work, | 
 |      * so is safe to call on your main thread. | 
 |      * | 
 |      * <p>Only one NDEF message can be pushed by the currently resumed activity. | 
 |      * If both {@link #setNdefPushMessage} and | 
 |      * {@link #setNdefPushMessageCallback} are set, then | 
 |      * the callback will take priority. | 
 |      * | 
 |      * <p>If neither {@link #setNdefPushMessage} or | 
 |      * {@link #setNdefPushMessageCallback} have been called for your activity, then | 
 |      * the Android OS may choose to send a default NDEF message on your behalf, | 
 |      * such as a URI for your application. | 
 |      * | 
 |      * <p>If {@link #setNdefPushMessage} is called with a null NDEF message, | 
 |      * and/or {@link #setNdefPushMessageCallback} is called with a null callback, | 
 |      * then NDEF push will be completely disabled for the specified activity(s). | 
 |      * This also disables any default NDEF message the Android OS would have | 
 |      * otherwise sent on your behalf for those activity(s). | 
 |      * | 
 |      * <p>If you want to prevent the Android OS from sending default NDEF | 
 |      * messages completely (for all activities), you can include a | 
 |      * {@code <meta-data>} element inside the {@code <application>} | 
 |      * element of your AndroidManifest.xml file, like this: | 
 |      * <pre> | 
 |      * <application ...> | 
 |      *     <meta-data android:name="android.nfc.disable_beam_default" | 
 |      *         android:value="true" /> | 
 |      * </application></pre> | 
 |      * | 
 |      * <p>The API allows for multiple activities to be specified at a time, | 
 |      * but it is strongly recommended to just register one at a time, | 
 |      * and to do so during the activity's {@link Activity#onCreate}. For example: | 
 |      * <pre> | 
 |      * protected void onCreate(Bundle savedInstanceState) { | 
 |      *     super.onCreate(savedInstanceState); | 
 |      *     NfcAdapter nfcAdapter = NfcAdapter.getDefaultAdapter(this); | 
 |      *     if (nfcAdapter == null) return;  // NFC not available on this device | 
 |      *     nfcAdapter.setNdefPushMessage(ndefMessage, this); | 
 |      * }</pre> | 
 |      * And that is it. Only one call per activity is necessary. The Android | 
 |      * OS will automatically release its references to the NDEF message and the | 
 |      * Activity object when it is destroyed if you follow this pattern. | 
 |      * | 
 |      * <p>If your Activity wants to dynamically generate an NDEF message, | 
 |      * then set a callback using {@link #setNdefPushMessageCallback} instead | 
 |      * of a static message. | 
 |      * | 
 |      * <p class="note">Do not pass in an Activity that has already been through | 
 |      * {@link Activity#onDestroy}. This is guaranteed if you call this API | 
 |      * during {@link Activity#onCreate}. | 
 |      * | 
 |      * <p class="note">For sending large content such as pictures and songs, | 
 |      * consider using {@link #setBeamPushUris}, which switches to alternate transports | 
 |      * such as Bluetooth to achieve a fast transfer rate. | 
 |      * | 
 |      * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission. | 
 |      * | 
 |      * @param message NDEF message to push over NFC, or null to disable | 
 |      * @param activity activity for which the NDEF message will be pushed | 
 |      * @param activities optional additional activities, however we strongly recommend | 
 |      *        to only register one at a time, and to do so in that activity's | 
 |      *        {@link Activity#onCreate} | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      * @deprecated this feature is deprecated. File sharing can work using other technology like | 
 |      * Bluetooth. | 
 |      */ | 
 |     @java.lang.Deprecated | 
 |     public void setNdefPushMessage(NdefMessage message, Activity activity, | 
 |             Activity ... activities) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |             if (!sHasBeamFeature) { | 
 |                 return; | 
 |             } | 
 |         } | 
 |         int targetSdkVersion = getSdkVersion(); | 
 |         try { | 
 |             if (activity == null) { | 
 |                 throw new NullPointerException("activity cannot be null"); | 
 |             } | 
 |             mNfcActivityManager.setNdefPushMessage(activity, message, 0); | 
 |             for (Activity a : activities) { | 
 |                 if (a == null) { | 
 |                     throw new NullPointerException("activities cannot contain null"); | 
 |                 } | 
 |                 mNfcActivityManager.setNdefPushMessage(a, message, 0); | 
 |             } | 
 |         } catch (IllegalStateException e) { | 
 |             if (targetSdkVersion < android.os.Build.VERSION_CODES.JELLY_BEAN) { | 
 |                 // Less strict on old applications - just log the error | 
 |                 Log.e(TAG, "Cannot call API with Activity that has already " + | 
 |                         "been destroyed", e); | 
 |             } else { | 
 |                 // Prevent new applications from making this mistake, re-throw | 
 |                 throw(e); | 
 |             } | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * @hide | 
 |      */ | 
 |     @SystemApi | 
 |     public void setNdefPushMessage(NdefMessage message, Activity activity, int flags) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |         } | 
 |         if (activity == null) { | 
 |             throw new NullPointerException("activity cannot be null"); | 
 |         } | 
 |         mNfcActivityManager.setNdefPushMessage(activity, message, flags); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Set a callback that dynamically generates NDEF messages to send using Android Beam (TM). | 
 |      * | 
 |      * <p>This method may be called at any time before {@link Activity#onDestroy}, | 
 |      * but the NDEF message callback can only occur when the | 
 |      * specified activity(s) are in resumed (foreground) state. The recommended | 
 |      * approach is to call this method during your Activity's | 
 |      * {@link Activity#onCreate} - see sample | 
 |      * code below. This method does not immediately perform any I/O or blocking work, | 
 |      * so is safe to call on your main thread. | 
 |      * | 
 |      * <p>Only one NDEF message can be pushed by the currently resumed activity. | 
 |      * If both {@link #setNdefPushMessage} and | 
 |      * {@link #setNdefPushMessageCallback} are set, then | 
 |      * the callback will take priority. | 
 |      * | 
 |      * <p>If neither {@link #setNdefPushMessage} or | 
 |      * {@link #setNdefPushMessageCallback} have been called for your activity, then | 
 |      * the Android OS may choose to send a default NDEF message on your behalf, | 
 |      * such as a URI for your application. | 
 |      * | 
 |      * <p>If {@link #setNdefPushMessage} is called with a null NDEF message, | 
 |      * and/or {@link #setNdefPushMessageCallback} is called with a null callback, | 
 |      * then NDEF push will be completely disabled for the specified activity(s). | 
 |      * This also disables any default NDEF message the Android OS would have | 
 |      * otherwise sent on your behalf for those activity(s). | 
 |      * | 
 |      * <p>If you want to prevent the Android OS from sending default NDEF | 
 |      * messages completely (for all activities), you can include a | 
 |      * {@code <meta-data>} element inside the {@code <application>} | 
 |      * element of your AndroidManifest.xml file, like this: | 
 |      * <pre> | 
 |      * <application ...> | 
 |      *     <meta-data android:name="android.nfc.disable_beam_default" | 
 |      *         android:value="true" /> | 
 |      * </application></pre> | 
 |      * | 
 |      * <p>The API allows for multiple activities to be specified at a time, | 
 |      * but it is strongly recommended to just register one at a time, | 
 |      * and to do so during the activity's {@link Activity#onCreate}. For example: | 
 |      * <pre> | 
 |      * protected void onCreate(Bundle savedInstanceState) { | 
 |      *     super.onCreate(savedInstanceState); | 
 |      *     NfcAdapter nfcAdapter = NfcAdapter.getDefaultAdapter(this); | 
 |      *     if (nfcAdapter == null) return;  // NFC not available on this device | 
 |      *     nfcAdapter.setNdefPushMessageCallback(callback, this); | 
 |      * }</pre> | 
 |      * And that is it. Only one call per activity is necessary. The Android | 
 |      * OS will automatically release its references to the callback and the | 
 |      * Activity object when it is destroyed if you follow this pattern. | 
 |      * | 
 |      * <p class="note">Do not pass in an Activity that has already been through | 
 |      * {@link Activity#onDestroy}. This is guaranteed if you call this API | 
 |      * during {@link Activity#onCreate}. | 
 |      * <p class="note">For sending large content such as pictures and songs, | 
 |      * consider using {@link #setBeamPushUris}, which switches to alternate transports | 
 |      * such as Bluetooth to achieve a fast transfer rate. | 
 |      * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission. | 
 |      * | 
 |      * @param callback callback, or null to disable | 
 |      * @param activity activity for which the NDEF message will be pushed | 
 |      * @param activities optional additional activities, however we strongly recommend | 
 |      *        to only register one at a time, and to do so in that activity's | 
 |      *        {@link Activity#onCreate} | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      * @deprecated this feature is deprecated. File sharing can work using other technology like | 
 |      * Bluetooth. | 
 |      */ | 
 |     @java.lang.Deprecated | 
 |     public void setNdefPushMessageCallback(CreateNdefMessageCallback callback, Activity activity, | 
 |             Activity ... activities) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |             if (!sHasBeamFeature) { | 
 |                 return; | 
 |             } | 
 |         } | 
 |         int targetSdkVersion = getSdkVersion(); | 
 |         try { | 
 |             if (activity == null) { | 
 |                 throw new NullPointerException("activity cannot be null"); | 
 |             } | 
 |             mNfcActivityManager.setNdefPushMessageCallback(activity, callback, 0); | 
 |             for (Activity a : activities) { | 
 |                 if (a == null) { | 
 |                     throw new NullPointerException("activities cannot contain null"); | 
 |                 } | 
 |                 mNfcActivityManager.setNdefPushMessageCallback(a, callback, 0); | 
 |             } | 
 |         } catch (IllegalStateException e) { | 
 |             if (targetSdkVersion < android.os.Build.VERSION_CODES.JELLY_BEAN) { | 
 |                 // Less strict on old applications - just log the error | 
 |                 Log.e(TAG, "Cannot call API with Activity that has already " + | 
 |                         "been destroyed", e); | 
 |             } else { | 
 |                 // Prevent new applications from making this mistake, re-throw | 
 |                 throw(e); | 
 |             } | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * @hide | 
 |      */ | 
 |     @UnsupportedAppUsage | 
 |     public void setNdefPushMessageCallback(CreateNdefMessageCallback callback, Activity activity, | 
 |             int flags) { | 
 |         if (activity == null) { | 
 |             throw new NullPointerException("activity cannot be null"); | 
 |         } | 
 |         mNfcActivityManager.setNdefPushMessageCallback(activity, callback, flags); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Set a callback on successful Android Beam (TM). | 
 |      * | 
 |      * <p>This method may be called at any time before {@link Activity#onDestroy}, | 
 |      * but the callback can only occur when the | 
 |      * specified activity(s) are in resumed (foreground) state. The recommended | 
 |      * approach is to call this method during your Activity's | 
 |      * {@link Activity#onCreate} - see sample | 
 |      * code below. This method does not immediately perform any I/O or blocking work, | 
 |      * so is safe to call on your main thread. | 
 |      * | 
 |      * <p>The API allows for multiple activities to be specified at a time, | 
 |      * but it is strongly recommended to just register one at a time, | 
 |      * and to do so during the activity's {@link Activity#onCreate}. For example: | 
 |      * <pre> | 
 |      * protected void onCreate(Bundle savedInstanceState) { | 
 |      *     super.onCreate(savedInstanceState); | 
 |      *     NfcAdapter nfcAdapter = NfcAdapter.getDefaultAdapter(this); | 
 |      *     if (nfcAdapter == null) return;  // NFC not available on this device | 
 |      *     nfcAdapter.setOnNdefPushCompleteCallback(callback, this); | 
 |      * }</pre> | 
 |      * And that is it. Only one call per activity is necessary. The Android | 
 |      * OS will automatically release its references to the callback and the | 
 |      * Activity object when it is destroyed if you follow this pattern. | 
 |      * | 
 |      * <p class="note">Do not pass in an Activity that has already been through | 
 |      * {@link Activity#onDestroy}. This is guaranteed if you call this API | 
 |      * during {@link Activity#onCreate}. | 
 |      * | 
 |      * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission. | 
 |      * | 
 |      * @param callback callback, or null to disable | 
 |      * @param activity activity for which the NDEF message will be pushed | 
 |      * @param activities optional additional activities, however we strongly recommend | 
 |      *        to only register one at a time, and to do so in that activity's | 
 |      *        {@link Activity#onCreate} | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      * @deprecated this feature is deprecated. File sharing can work using other technology like | 
 |      * Bluetooth. | 
 |      */ | 
 |     @java.lang.Deprecated | 
 |     public void setOnNdefPushCompleteCallback(OnNdefPushCompleteCallback callback, | 
 |             Activity activity, Activity ... activities) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |             if (!sHasBeamFeature) { | 
 |                 return; | 
 |             } | 
 |         } | 
 |         int targetSdkVersion = getSdkVersion(); | 
 |         try { | 
 |             if (activity == null) { | 
 |                 throw new NullPointerException("activity cannot be null"); | 
 |             } | 
 |             mNfcActivityManager.setOnNdefPushCompleteCallback(activity, callback); | 
 |             for (Activity a : activities) { | 
 |                 if (a == null) { | 
 |                     throw new NullPointerException("activities cannot contain null"); | 
 |                 } | 
 |                 mNfcActivityManager.setOnNdefPushCompleteCallback(a, callback); | 
 |             } | 
 |         } catch (IllegalStateException e) { | 
 |             if (targetSdkVersion < android.os.Build.VERSION_CODES.JELLY_BEAN) { | 
 |                 // Less strict on old applications - just log the error | 
 |                 Log.e(TAG, "Cannot call API with Activity that has already " + | 
 |                         "been destroyed", e); | 
 |             } else { | 
 |                 // Prevent new applications from making this mistake, re-throw | 
 |                 throw(e); | 
 |             } | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Enable foreground dispatch to the given Activity. | 
 |      * | 
 |      * <p>This will give give priority to the foreground activity when | 
 |      * dispatching a discovered {@link Tag} to an application. | 
 |      * | 
 |      * <p>If any IntentFilters are provided to this method they are used to match dispatch Intents | 
 |      * for both the {@link NfcAdapter#ACTION_NDEF_DISCOVERED} and | 
 |      * {@link NfcAdapter#ACTION_TAG_DISCOVERED}. Since {@link NfcAdapter#ACTION_TECH_DISCOVERED} | 
 |      * relies on meta data outside of the IntentFilter matching for that dispatch Intent is handled | 
 |      * by passing in the tech lists separately. Each first level entry in the tech list represents | 
 |      * an array of technologies that must all be present to match. If any of the first level sets | 
 |      * match then the dispatch is routed through the given PendingIntent. In other words, the second | 
 |      * level is ANDed together and the first level entries are ORed together. | 
 |      * | 
 |      * <p>If you pass {@code null} for both the {@code filters} and {@code techLists} parameters | 
 |      * that acts a wild card and will cause the foreground activity to receive all tags via the | 
 |      * {@link NfcAdapter#ACTION_TAG_DISCOVERED} intent. | 
 |      * | 
 |      * <p>This method must be called from the main thread, and only when the activity is in the | 
 |      * foreground (resumed). Also, activities must call {@link #disableForegroundDispatch} before | 
 |      * the completion of their {@link Activity#onPause} callback to disable foreground dispatch | 
 |      * after it has been enabled. | 
 |      * | 
 |      * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission. | 
 |      * | 
 |      * @param activity the Activity to dispatch to | 
 |      * @param intent the PendingIntent to start for the dispatch | 
 |      * @param filters the IntentFilters to override dispatching for, or null to always dispatch | 
 |      * @param techLists the tech lists used to perform matching for dispatching of the | 
 |      *      {@link NfcAdapter#ACTION_TECH_DISCOVERED} intent | 
 |      * @throws IllegalStateException if the Activity is not currently in the foreground | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      */ | 
 |     public void enableForegroundDispatch(Activity activity, PendingIntent intent, | 
 |             IntentFilter[] filters, String[][] techLists) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |         } | 
 |         if (activity == null || intent == null) { | 
 |             throw new NullPointerException(); | 
 |         } | 
 |         if (!activity.isResumed()) { | 
 |             throw new IllegalStateException("Foreground dispatch can only be enabled " + | 
 |                     "when your activity is resumed"); | 
 |         } | 
 |         try { | 
 |             TechListParcel parcel = null; | 
 |             if (techLists != null && techLists.length > 0) { | 
 |                 parcel = new TechListParcel(techLists); | 
 |             } | 
 |             ActivityThread.currentActivityThread().registerOnActivityPausedListener(activity, | 
 |                     mForegroundDispatchListener); | 
 |             sService.setForegroundDispatch(intent, filters, parcel); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Disable foreground dispatch to the given activity. | 
 |      * | 
 |      * <p>After calling {@link #enableForegroundDispatch}, an activity | 
 |      * must call this method before its {@link Activity#onPause} callback | 
 |      * completes. | 
 |      * | 
 |      * <p>This method must be called from the main thread. | 
 |      * | 
 |      * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission. | 
 |      * | 
 |      * @param activity the Activity to disable dispatch to | 
 |      * @throws IllegalStateException if the Activity has already been paused | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      */ | 
 |     public void disableForegroundDispatch(Activity activity) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |         } | 
 |         ActivityThread.currentActivityThread().unregisterOnActivityPausedListener(activity, | 
 |                 mForegroundDispatchListener); | 
 |         disableForegroundDispatchInternal(activity, false); | 
 |     } | 
 |  | 
 |     OnActivityPausedListener mForegroundDispatchListener = new OnActivityPausedListener() { | 
 |         @Override | 
 |         public void onPaused(Activity activity) { | 
 |             disableForegroundDispatchInternal(activity, true); | 
 |         } | 
 |     }; | 
 |  | 
 |     void disableForegroundDispatchInternal(Activity activity, boolean force) { | 
 |         try { | 
 |             sService.setForegroundDispatch(null, null, null); | 
 |             if (!force && !activity.isResumed()) { | 
 |                 throw new IllegalStateException("You must disable foreground dispatching " + | 
 |                         "while your activity is still resumed"); | 
 |             } | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Limit the NFC controller to reader mode while this Activity is in the foreground. | 
 |      * | 
 |      * <p>In this mode the NFC controller will only act as an NFC tag reader/writer, | 
 |      * thus disabling any peer-to-peer (Android Beam) and card-emulation modes of | 
 |      * the NFC adapter on this device. | 
 |      * | 
 |      * <p>Use {@link #FLAG_READER_SKIP_NDEF_CHECK} to prevent the platform from | 
 |      * performing any NDEF checks in reader mode. Note that this will prevent the | 
 |      * {@link Ndef} tag technology from being enumerated on the tag, and that | 
 |      * NDEF-based tag dispatch will not be functional. | 
 |      * | 
 |      * <p>For interacting with tags that are emulated on another Android device | 
 |      * using Android's host-based card-emulation, the recommended flags are | 
 |      * {@link #FLAG_READER_NFC_A} and {@link #FLAG_READER_SKIP_NDEF_CHECK}. | 
 |      * | 
 |      * @param activity the Activity that requests the adapter to be in reader mode | 
 |      * @param callback the callback to be called when a tag is discovered | 
 |      * @param flags Flags indicating poll technologies and other optional parameters | 
 |      * @param extras Additional extras for configuring reader mode. | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      */ | 
 |     public void enableReaderMode(Activity activity, ReaderCallback callback, int flags, | 
 |             Bundle extras) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |         } | 
 |         mNfcActivityManager.enableReaderMode(activity, callback, flags, extras); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Restore the NFC adapter to normal mode of operation: supporting | 
 |      * peer-to-peer (Android Beam), card emulation, and polling for | 
 |      * all supported tag technologies. | 
 |      * | 
 |      * @param activity the Activity that currently has reader mode enabled | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      */ | 
 |     public void disableReaderMode(Activity activity) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |         } | 
 |         mNfcActivityManager.disableReaderMode(activity); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Manually invoke Android Beam to share data. | 
 |      * | 
 |      * <p>The Android Beam animation is normally only shown when two NFC-capable | 
 |      * devices come into range. | 
 |      * By calling this method, an Activity can invoke the Beam animation directly | 
 |      * even if no other NFC device is in range yet. The Beam animation will then | 
 |      * prompt the user to tap another NFC-capable device to complete the data | 
 |      * transfer. | 
 |      * | 
 |      * <p>The main advantage of using this method is that it avoids the need for the | 
 |      * user to tap the screen to complete the transfer, as this method already | 
 |      * establishes the direction of the transfer and the consent of the user to | 
 |      * share data. Callers are responsible for making sure that the user has | 
 |      * consented to sharing data on NFC tap. | 
 |      * | 
 |      * <p>Note that to use this method, the passed in Activity must have already | 
 |      * set data to share over Beam by using method calls such as | 
 |      * {@link #setNdefPushMessageCallback} or | 
 |      * {@link #setBeamPushUrisCallback}. | 
 |      * | 
 |      * @param activity the current foreground Activity that has registered data to share | 
 |      * @return whether the Beam animation was successfully invoked | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      * @deprecated this feature is deprecated. File sharing can work using other technology like | 
 |      * Bluetooth. | 
 |      */ | 
 |     @java.lang.Deprecated | 
 |     public boolean invokeBeam(Activity activity) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |             if (!sHasBeamFeature) { | 
 |                 return false; | 
 |             } | 
 |         } | 
 |         if (activity == null) { | 
 |             throw new NullPointerException("activity may not be null."); | 
 |         } | 
 |         enforceResumed(activity); | 
 |         try { | 
 |             sService.invokeBeam(); | 
 |             return true; | 
 |         } catch (RemoteException e) { | 
 |             Log.e(TAG, "invokeBeam: NFC process has died."); | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * @hide | 
 |      */ | 
 |     public boolean invokeBeam(BeamShareData shareData) { | 
 |         try { | 
 |             Log.e(TAG, "invokeBeamInternal()"); | 
 |             sService.invokeBeamInternal(shareData); | 
 |             return true; | 
 |         } catch (RemoteException e) { | 
 |             Log.e(TAG, "invokeBeam: NFC process has died."); | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Enable NDEF message push over NFC while this Activity is in the foreground. | 
 |      * | 
 |      * <p>You must explicitly call this method every time the activity is | 
 |      * resumed, and you must call {@link #disableForegroundNdefPush} before | 
 |      * your activity completes {@link Activity#onPause}. | 
 |      * | 
 |      * <p>Strongly recommend to use the new {@link #setNdefPushMessage} | 
 |      * instead: it automatically hooks into your activity life-cycle, | 
 |      * so you do not need to call enable/disable in your onResume/onPause. | 
 |      * | 
 |      * <p>For NDEF push to function properly the other NFC device must | 
 |      * support either NFC Forum's SNEP (Simple Ndef Exchange Protocol), or | 
 |      * Android's "com.android.npp" (Ndef Push Protocol). This was optional | 
 |      * on Gingerbread level Android NFC devices, but SNEP is mandatory on | 
 |      * Ice-Cream-Sandwich and beyond. | 
 |      * | 
 |      * <p>This method must be called from the main thread. | 
 |      * | 
 |      * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission. | 
 |      * | 
 |      * @param activity foreground activity | 
 |      * @param message a NDEF Message to push over NFC | 
 |      * @throws IllegalStateException if the activity is not currently in the foreground | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      * @deprecated use {@link #setNdefPushMessage} instead | 
 |      */ | 
 |     @Deprecated | 
 |     public void enableForegroundNdefPush(Activity activity, NdefMessage message) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |             if (!sHasBeamFeature) { | 
 |                 return; | 
 |             } | 
 |         } | 
 |         if (activity == null || message == null) { | 
 |             throw new NullPointerException(); | 
 |         } | 
 |         enforceResumed(activity); | 
 |         mNfcActivityManager.setNdefPushMessage(activity, message, 0); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Disable NDEF message push over P2P. | 
 |      * | 
 |      * <p>After calling {@link #enableForegroundNdefPush}, an activity | 
 |      * must call this method before its {@link Activity#onPause} callback | 
 |      * completes. | 
 |      * | 
 |      * <p>Strongly recommend to use the new {@link #setNdefPushMessage} | 
 |      * instead: it automatically hooks into your activity life-cycle, | 
 |      * so you do not need to call enable/disable in your onResume/onPause. | 
 |      * | 
 |      * <p>This method must be called from the main thread. | 
 |      * | 
 |      * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission. | 
 |      * | 
 |      * @param activity the Foreground activity | 
 |      * @throws IllegalStateException if the Activity has already been paused | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      * @deprecated use {@link #setNdefPushMessage} instead | 
 |      */ | 
 |     @Deprecated | 
 |     public void disableForegroundNdefPush(Activity activity) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |             if (!sHasBeamFeature) { | 
 |                 return; | 
 |             } | 
 |         } | 
 |         if (activity == null) { | 
 |             throw new NullPointerException(); | 
 |         } | 
 |         enforceResumed(activity); | 
 |         mNfcActivityManager.setNdefPushMessage(activity, null, 0); | 
 |         mNfcActivityManager.setNdefPushMessageCallback(activity, null, 0); | 
 |         mNfcActivityManager.setOnNdefPushCompleteCallback(activity, null); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Sets Secure NFC feature. | 
 |      * <p>This API is for the Settings application. | 
 |      * @return True if successful | 
 |      * @hide | 
 |      */ | 
 |     @SystemApi | 
 |     @RequiresPermission(android.Manifest.permission.WRITE_SECURE_SETTINGS) | 
 |     public boolean enableSecureNfc(boolean enable) { | 
 |         if (!sHasNfcFeature) { | 
 |             throw new UnsupportedOperationException(); | 
 |         } | 
 |         try { | 
 |             return sService.setNfcSecure(enable); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Checks if the device supports Secure NFC functionality. | 
 |      * | 
 |      * @return True if device supports Secure NFC, false otherwise | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      */ | 
 |     public boolean isSecureNfcSupported() { | 
 |         if (!sHasNfcFeature) { | 
 |             throw new UnsupportedOperationException(); | 
 |         } | 
 |         try { | 
 |             return sService.deviceSupportsNfcSecure(); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Checks Secure NFC feature is enabled. | 
 |      * | 
 |      * @return True if Secure NFC is enabled, false otherwise | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      * @throws UnsupportedOperationException if device doesn't support | 
 |      *         Secure NFC functionality. {@link #isSecureNfcSupported} | 
 |      */ | 
 |     public boolean isSecureNfcEnabled() { | 
 |         if (!sHasNfcFeature) { | 
 |             throw new UnsupportedOperationException(); | 
 |         } | 
 |         try { | 
 |             return sService.isNfcSecureEnabled(); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Enable NDEF Push feature. | 
 |      * <p>This API is for the Settings application. | 
 |      * @hide | 
 |      */ | 
 |     @SystemApi | 
 |     @RequiresPermission(android.Manifest.permission.WRITE_SECURE_SETTINGS) | 
 |     public boolean enableNdefPush() { | 
 |         if (!sHasNfcFeature) { | 
 |             throw new UnsupportedOperationException(); | 
 |         } | 
 |         try { | 
 |             return sService.enableNdefPush(); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Disable NDEF Push feature. | 
 |      * <p>This API is for the Settings application. | 
 |      * @hide | 
 |      */ | 
 |     @SystemApi | 
 |     @RequiresPermission(android.Manifest.permission.WRITE_SECURE_SETTINGS) | 
 |     public boolean disableNdefPush() { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |         } | 
 |         try { | 
 |             return sService.disableNdefPush(); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Return true if the NDEF Push (Android Beam) feature is enabled. | 
 |      * <p>This function will return true only if both NFC is enabled, and the | 
 |      * NDEF Push feature is enabled. | 
 |      * <p>Note that if NFC is enabled but NDEF Push is disabled then this | 
 |      * device can still <i>receive</i> NDEF messages, it just cannot send them. | 
 |      * <p>Applications cannot directly toggle the NDEF Push feature, but they | 
 |      * can request Settings UI allowing the user to toggle NDEF Push using | 
 |      * <code>startActivity(new Intent(Settings.ACTION_NFCSHARING_SETTINGS))</code> | 
 |      * <p>Example usage in an Activity that requires NDEF Push: | 
 |      * <p><pre> | 
 |      * protected void onResume() { | 
 |      *     super.onResume(); | 
 |      *     if (!nfcAdapter.isEnabled()) { | 
 |      *         startActivity(new Intent(Settings.ACTION_NFC_SETTINGS)); | 
 |      *     } else if (!nfcAdapter.isNdefPushEnabled()) { | 
 |      *         startActivity(new Intent(Settings.ACTION_NFCSHARING_SETTINGS)); | 
 |      *     } | 
 |      * }</pre> | 
 |      * | 
 |      * @see android.provider.Settings#ACTION_NFCSHARING_SETTINGS | 
 |      * @return true if NDEF Push feature is enabled | 
 |      * @throws UnsupportedOperationException if FEATURE_NFC is unavailable. | 
 |      * @deprecated this feature is deprecated. File sharing can work using other technology like | 
 |      * Bluetooth. | 
 |      */ | 
 |     @java.lang.Deprecated | 
 |  | 
 |     public boolean isNdefPushEnabled() { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |             if (!sHasBeamFeature) { | 
 |                 return false; | 
 |             } | 
 |         } | 
 |         try { | 
 |             return sService.isNdefPushEnabled(); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Signals that you are no longer interested in communicating with an NFC tag | 
 |      * for as long as it remains in range. | 
 |      * | 
 |      * All future attempted communication to this tag will fail with {@link IOException}. | 
 |      * The NFC controller will be put in a low-power polling mode, allowing the device | 
 |      * to save power in cases where it's "attached" to a tag all the time (e.g. a tag in | 
 |      * car dock). | 
 |      * | 
 |      * Additionally the debounceMs parameter allows you to specify for how long the tag needs | 
 |      * to have gone out of range, before it will be dispatched again. | 
 |      * | 
 |      * Note: the NFC controller typically polls at a pretty slow interval (100 - 500 ms). | 
 |      * This means that if the tag repeatedly goes in and out of range (for example, in | 
 |      * case of a flaky connection), and the controller happens to poll every time the | 
 |      * tag is out of range, it *will* re-dispatch the tag after debounceMs, despite the tag | 
 |      * having been "in range" during the interval. | 
 |      * | 
 |      * Note 2: if a tag with another UID is detected after this API is called, its effect | 
 |      * will be cancelled; if this tag shows up before the amount of time specified in | 
 |      * debounceMs, it will be dispatched again. | 
 |      * | 
 |      * Note 3: some tags have a random UID, in which case this API won't work reliably. | 
 |      * | 
 |      * @param tag        the {@link android.nfc.Tag Tag} to ignore. | 
 |      * @param debounceMs minimum amount of time the tag needs to be out of range before being | 
 |      *                   dispatched again. | 
 |      * @param tagRemovedListener listener to be called when the tag is removed from the field. | 
 |      *                           Note that this will only be called if the tag has been out of range | 
 |      *                           for at least debounceMs, or if another tag came into range before | 
 |      *                           debounceMs. May be null in case you don't want a callback. | 
 |      * @param handler the {@link android.os.Handler Handler} that will be used for delivering | 
 |      *                the callback. if the handler is null, then the thread used for delivering | 
 |      *                the callback is unspecified. | 
 |      * @return false if the tag couldn't be found (or has already gone out of range), true otherwise | 
 |      */ | 
 |     public boolean ignore(final Tag tag, int debounceMs, | 
 |                           final OnTagRemovedListener tagRemovedListener, final Handler handler) { | 
 |         ITagRemovedCallback.Stub iListener = null; | 
 |         if (tagRemovedListener != null) { | 
 |             iListener = new ITagRemovedCallback.Stub() { | 
 |                 @Override | 
 |                 public void onTagRemoved() throws RemoteException { | 
 |                     if (handler != null) { | 
 |                         handler.post(new Runnable() { | 
 |                             @Override | 
 |                             public void run() { | 
 |                                 tagRemovedListener.onTagRemoved(); | 
 |                             } | 
 |                         }); | 
 |                     } else { | 
 |                         tagRemovedListener.onTagRemoved(); | 
 |                     } | 
 |                     synchronized (mLock) { | 
 |                         mTagRemovedListener = null; | 
 |                     } | 
 |                 } | 
 |             }; | 
 |         } | 
 |         synchronized (mLock) { | 
 |             mTagRemovedListener = iListener; | 
 |         } | 
 |         try { | 
 |             return sService.ignore(tag.getServiceHandle(), debounceMs, iListener); | 
 |         } catch (RemoteException e) { | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Inject a mock NFC tag.<p> | 
 |      * Used for testing purposes. | 
 |      * <p class="note">Requires the | 
 |      * {@link android.Manifest.permission#WRITE_SECURE_SETTINGS} permission. | 
 |      * @hide | 
 |      */ | 
 |     public void dispatch(Tag tag) { | 
 |         if (tag == null) { | 
 |             throw new NullPointerException("tag cannot be null"); | 
 |         } | 
 |         try { | 
 |             sService.dispatch(tag); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * @hide | 
 |      */ | 
 |     public void setP2pModes(int initiatorModes, int targetModes) { | 
 |         try { | 
 |             sService.setP2pModes(initiatorModes, targetModes); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * Registers a new NFC unlock handler with the NFC service. | 
 |      * | 
 |      * <p />NFC unlock handlers are intended to unlock the keyguard in the presence of a trusted | 
 |      * NFC device. The handler should return true if it successfully authenticates the user and | 
 |      * unlocks the keyguard. | 
 |      * | 
 |      * <p /> The parameter {@code tagTechnologies} determines which Tag technologies will be polled for | 
 |      * at the lockscreen. Polling for less tag technologies reduces latency, and so it is | 
 |      * strongly recommended to only provide the Tag technologies that the handler is expected to | 
 |      * receive. There must be at least one tag technology provided, otherwise the unlock handler | 
 |      * is ignored. | 
 |      * | 
 |      * @hide | 
 |      */ | 
 |     @SystemApi | 
 |     @RequiresPermission(android.Manifest.permission.WRITE_SECURE_SETTINGS) | 
 |     public boolean addNfcUnlockHandler(final NfcUnlockHandler unlockHandler, | 
 |                                        String[] tagTechnologies) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |         } | 
 |         // If there are no tag technologies, don't bother adding unlock handler | 
 |         if (tagTechnologies.length == 0) { | 
 |             return false; | 
 |         } | 
 |  | 
 |         try { | 
 |             synchronized (mLock) { | 
 |                 if (mNfcUnlockHandlers.containsKey(unlockHandler)) { | 
 |                     // update the tag technologies | 
 |                     sService.removeNfcUnlockHandler(mNfcUnlockHandlers.get(unlockHandler)); | 
 |                     mNfcUnlockHandlers.remove(unlockHandler); | 
 |                 } | 
 |  | 
 |                 INfcUnlockHandler.Stub iHandler = new INfcUnlockHandler.Stub() { | 
 |                     @Override | 
 |                     public boolean onUnlockAttempted(Tag tag) throws RemoteException { | 
 |                         return unlockHandler.onUnlockAttempted(tag); | 
 |                     } | 
 |                 }; | 
 |  | 
 |                 sService.addNfcUnlockHandler(iHandler, | 
 |                         Tag.getTechCodesFromStrings(tagTechnologies)); | 
 |                 mNfcUnlockHandlers.put(unlockHandler, iHandler); | 
 |             } | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } catch (IllegalArgumentException e) { | 
 |             Log.e(TAG, "Unable to register LockscreenDispatch", e); | 
 |             return false; | 
 |         } | 
 |  | 
 |         return true; | 
 |     } | 
 |  | 
 |     /** | 
 |      * Removes a previously registered unlock handler. Also removes the tag technologies | 
 |      * associated with the removed unlock handler. | 
 |      * | 
 |      * @hide | 
 |      */ | 
 |     @SystemApi | 
 |     @RequiresPermission(android.Manifest.permission.WRITE_SECURE_SETTINGS) | 
 |     public boolean removeNfcUnlockHandler(NfcUnlockHandler unlockHandler) { | 
 |         synchronized (NfcAdapter.class) { | 
 |             if (!sHasNfcFeature) { | 
 |                 throw new UnsupportedOperationException(); | 
 |             } | 
 |         } | 
 |         try { | 
 |             synchronized (mLock) { | 
 |                 if (mNfcUnlockHandlers.containsKey(unlockHandler)) { | 
 |                     sService.removeNfcUnlockHandler(mNfcUnlockHandlers.remove(unlockHandler)); | 
 |                 } | 
 |  | 
 |                 return true; | 
 |             } | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return false; | 
 |         } | 
 |     } | 
 |  | 
 |     /** | 
 |      * @hide | 
 |      */ | 
 |     @UnsupportedAppUsage | 
 |     public INfcAdapterExtras getNfcAdapterExtrasInterface() { | 
 |         if (mContext == null) { | 
 |             throw new UnsupportedOperationException("You need a context on NfcAdapter to use the " | 
 |                     + " NFC extras APIs"); | 
 |         } | 
 |         try { | 
 |             return sService.getNfcAdapterExtrasInterface(mContext.getPackageName()); | 
 |         } catch (RemoteException e) { | 
 |             attemptDeadServiceRecovery(e); | 
 |             return null; | 
 |         } | 
 |     } | 
 |  | 
 |     void enforceResumed(Activity activity) { | 
 |         if (!activity.isResumed()) { | 
 |             throw new IllegalStateException("API cannot be called while activity is paused"); | 
 |         } | 
 |     } | 
 |  | 
 |     int getSdkVersion() { | 
 |         if (mContext == null) { | 
 |             return android.os.Build.VERSION_CODES.GINGERBREAD; // best guess | 
 |         } else { | 
 |             return mContext.getApplicationInfo().targetSdkVersion; | 
 |         } | 
 |     } | 
 | } |